Abstract: A method for limiting baro-inertial vertical speed correction, baro-inertial vertical speed being calculated by a baro-inertial loop implemented by a processor included in an airborne system further including an accelerometer and a barometric altimeter, the loop taking a vertical acceleration and a barometric altitude as input and being configured so as: to provide at least one altitude and the vertical speed; to correct the altitude and the vertical speed on the basis of the barometric altitude, a position correction gain, a vertical speed correction gain and a vertical acceleration correction gain. The method includes limiting vertical speed correction when the absolute value of the difference between the barometric altitude and the altitude exceeds a predetermined threshold, the limiting vertical speed correction including modification of the position correction gain.

Abstract: A method for navigating a carrier using a Kalman filter estimating a navigation state of a carrier, comprising: obtaining, from a signal transmitted by the satellite and subsequently received by the carrier, a delta range measured between the carrier and a satellite and another measured kinematic datum which is associated with the satellite, generating, from position data for the carrier and the satellite in the navigation state, an estimated delta range between the carrier and the satellite, calculating, using the delta ranges, a delta range innovation associated with the satellite, carrying out a test on the delta range innovation, the test result indicating whether or not the signal was a multi-path signal, using, by means of the filter, the kinematic datum as an observation to update the navigation state provided that the test result indicates that the signal was not a multi-path signal.

Abstract: A method comprising steps of: performing spatial filtering (104, 204) causing an attenuation of power of radio signals received by an antenna system in an angular sector (A); detecting (106, 206, 210) that a radio signal is received by the antenna system while the angular sector (A) includes a direction pointing at a satellite (S1) forming part of a constellation of positioning satellites, that the received radio signal is not subject to the attenuation caused by the spatial filtering, and that the received radio signal is in the form of a positioning signal emanating from the satellite (S1); and, following the detection, implementing processing (112, 114, 212, 214) under the assumption that the antenna system has fallen victim to decoying.

Abstract: A navigation method based on satellite positioning data and non-satellite positioning data includes the following steps of: computing a first reference navigation that is hybridised on the basis of non-satellite positioning data and satellite positioning data, the first reference navigation being reset on the satellite positioning data; performing a statistical analysis of the positional corrections provided by the first reference navigation and deducing therefrom the existence or the absence of a deception operation of the satellite signal receiver. A navigation system for implementing this method is disclosed.

Abstract: A navigation method based on satellite and inertial positioning data includes the following steps of computing: a first reference navigation, that is hybridised on the basis of inertial positioning data with positional corrections determined on the basis of satellite positioning data; a second reference navigation, that is hybridised on the basis of inertial positioning data; an emergency navigation on the basis of the second reference navigation, reset on the operational navigation then corrected by means of the positional corrections provided by the first reference navigation. A navigation system for implementing this method is also disclosed.

Abstract: A method for statistically correcting the estimation of the state X of a system, the state X including a physical quantity, correcting the estimation of this state X being carried out on the basis of a plurality of observations Yi relating to this state X, each observation being obtained by a different measurement relating to at least one physical quantity, the method being implemented by a device including a calculator, the method including determining for each observation Yi, the difference between the observation Yi and the estimated state referred to as innovation Zi, using the relationship Zi=Yi?HX where H is the observation matrix associated with the statistical filter considered; associating an ordering parameter with each observation Yi, the ordering parameter being given by the relationship Ordi=|Zref?Zi| where Zref is a predetermined reference value; classifying the measurements in ascending order of the ordering parameter associated therewith; and correcting errors on the estimations using the stat

Abstract: A method for navigating a carrier using a Kalman filter estimating a navigation state of a carrier, comprising: obtaining, from a signal transmitted by the satellite and subsequently received by the carrier, a delta range measured between the carrier and a satellite and another measured kinematic datum which is associated with the satellite, generating, from position data for the carrier and the satellite in the navigation state, an estimated delta range between the carrier and the satellite, calculating, using the delta ranges, a delta range innovation associated with the satellite, carrying out a test on the delta range innovation, the test result indicating whether or not the signal was a multi-path signal, using, by means of the filter, the kinematic datum as an observation to update the navigation state provided that the test result indicates that the signal was not a multi-path signal.

Abstract: A method of performing a navigation calculation on the basis of a hybrid inertial navigation system on board a vehicle includes performing a hybrid first navigation calculation and an inertial second navigation calculation, calculating in real time a difference between the first navigation calculation and the second navigation calculation, and subjecting the difference to lowpass filtering having a convergence time longer than a period of the Kalman filter and shorter than the Schuler period, and using the filtered difference to correct the second navigation calculation.

Abstract: A method of performing a navigation calculation on the basis of a hybrid inertial navigation system on board a vehicle, the method comprising the steps of: performing a hybrid first navigation calculation and an inertial second navigation calculation; calculating in real time a difference between the first navigation calculation and the second navigation calculation, and subjecting the difference to lowpass filtering having a convergence time longer than a period of the Kalman filter and shorter than the Schuler period; and using the filtered difference to correct the second navigation calculation.

Abstract: An inertial navigation system using loose coupling hybridization of inertial measurements by utilizing measurements supplied by a satellite-positioning receiver which utilizes signals sent by a plurality of satellites distributed across at least two separate satellite subsets and calculates at least two navigation solutions, each navigation solution being calculated by means of signals sent by the satellites of one of the subsets. The inertial navigation system includes a hybridization module using each of the at least two calculated navigation solutions. A satellite failure detector is configured to compare the hybrid navigation solutions and where applicable detect incoherence between said hybrid navigation solutions. The hybridization module is configured to stop execution of hybridization following detection of incoherence between the hybrid navigation solutions when the origin of the incoherence cannot be determined.

Abstract: An inertial navigation system using loose coupling hybridization of inertial measurements by utilizing measurements supplied by a satellite-positioning receiver which utilizes signals sent by a plurality of satellites distributed across at least two separate satellite subsets and calculates at least two navigation solutions, each navigation solution being calculated by means of signals sent by the satellites of one of the subsets. The inertial navigation system includes a hybridization module using each of the at least two calculated navigation solutions. A satellite failure detector is configured to compare the hybrid navigation solutions and where applicable detect incoherence between said hybrid navigation solutions. The hybridization module is configured to stop execution of hybridization following detection of incoherence between the hybrid navigation solutions when the origin of the incoherence cannot be determined.